In a photomechanical process, it is required to obtain a superhigh contrast property (particularly .gamma. of 10 or more) in order to improve reproduction of continuous tone image by a dot image process or reproduction of line original. To this end, a combination of a light-sensitive material comprising a silver chloride emulsion or a silver chlorobromide emulsion having a high silver chloride content and a hydroquinone developing solution having an extremely low effective concentration of sulfite ions (generally not more than 0.1 mol/liter) (infectious developing solution) has heretofore been generally used. However, such an infectious developing solution is disadvantageous in that it is extremely unstable due to its low sulfite ion concentration, making it impossible to be stored for more than 3 days.
Examples of improved methods for attaining a superhigh photographic property by using a stable developing solution include a method using specific hydrazine compounds as described in U.S. Pat. No. 4,224,401, etc. In this method, a high concentration of sulfite ion is allowed to be present in the developing solution. This protects the developing solution against aerial oxidation, improving its stability.
Japanese patent application (OPI) No. 106244/81 (the term "OPI" as used herein refers to a "published unexamined Japanese patent application") proposes that an amine compound be added to the developing solution in order to further improve the superhigh contrast image-forming method using the above-described hydrazine compounds so that a negative image having a high gamma value can be obtained by using a developing solution having a lower pH value.
However, this method is disadvantageous in that the use of a relatively high amount of amines causes generation of odor peculiar to amines and makes it difficult to keep the concentration of amines constant. This method is also disadvantageous in that a long developing time is required to obtain the desired results due to its insufficient developing rate.
In order to solve these problems, it is proposed that amine compounds as described in Japanese patent application (OPI) No. 140340/85 be incorporated in the light-sensitive material.
However, it was found that the specific amine compounds described in the above-described patent are disadvantageous in that they effuse into the developing solution and therefore exert an adverse effect on other photographic light-sensitive materials and that they easily cause a problem called "black pepper" in the art when the system using the hydrazine derivative is employed.
The term "black pepper" as used herein means a black spot produced on a nonimage portion (e.g., portion between dots). This defect usually occurs when the concentration of sulfite ions used as preservatives is decreased or the pH value of the developing solution is raised due to fatigue of the developing solution.